The previous owner of our PSC 31 had a Marine Air 16000 BTU reverse cycle unit installed.The raw water intake is just aft of the engine intake and also serves the washdown pump. The system is installed in the wet locker aft of the head. The discharge thruhull is in the same locker between the electric bilge pump thruhull and the propane locker drain thruhull.
I always considered AC on a boat to be a luxury, but have been converted.
PSC 31 #83